Dielectric fittings or isolators are known in the art and have found use in many applications, ranging from natural gas pipelines, where they isolate monitoring instruments from the effects of electrical current and interrupt cathodic current flow while permitting fluid flow, to providing a conduit for transferring liquid through selected locations as required or aircraft bulkhead structures. In the latter usage, the dielectric fitting contains integral fitting connections on both sides of the aircraft bulkhead that permit connections of tubes, hoses, or other fluid-carrying components. Such a dielectric fitting also provides a high electrical resistance path that limits electrical current flow between the two fitting connections, but allows for the gradual dissipation of electrostatic charge.
Thus, the primary functions of a dielectric fitting, also referred to as a static dissipative isolator, is to dissipate the electrical energy from static charges caused, in part, by fluid movements and to limit electrical current flow caused by the indirect effects of lightning, at such an occurrence. These fittings have the equally important secondary function of providing a safe fluid passage for the fluid passing through the fuel tank or other areas of the aircraft.